Seychelles -LRB- CNN -RRB- -- The pristine waters of the Seychelles , a glittering necklace of coralline and granitic islands scattered on the Indian Ocean , have long beguiled jet-setters and eco-conscious visitors from around the world , turning the idyllic archipelago into a popular travel destination .

But as well as boosting the tiny nation 's tourism revenues , the high seas off the east coast of Africa have also helped create another strategic industry : fishing .

A major economic pillar , fishing is the second biggest contributor to the Seychelles ' finances after tourism . Over the last two decades , the sector 's products have accounted for more than 90 % of the country 's merchandise exports by value , supplying international markets with items such as canned tuna , also known as the Seychelles ' `` blue gold . ''

But in recent years , the fishing industry has come under severe threat as a result of the ongoing risk posed by Somali pirates roaming the waters off the Horn of Africa .

`` It 's a big problem , '' explains major Jean Attala , deputy operations officer of the Seychelles coast guard . `` Anything that disrupts the tourism or fishing industry or the maritime equilibrium is a very big problem for us , '' he adds .

Read this : The global cost of piracy

To deal with the threat of piracy , the country 's authorities had to change the way they manage their waters in recent years . As part of this increased security drive , the Seychelles coast guard has intensified its patrolling efforts , with fast-attack armed vessels monitoring a newly defined zone for fishing .

But there are just four such vessels in the Seychelles ' entire fleet . It 's a small nation in terms of landmass , but with its oceans , it is nearly twice the size of France . `` This is not adequate to cover such a large area , '' says Attala . `` We need more assets and build up more our capacity to deal with the issue . ''

Local fishermen are restricted from sailing beyond the designated area 's perimeter , several dozen miles outside the main port .

Analysts say that fishing boats are of particular importance to pirates because they can be used as floating bases from which to launch further attacks .

But while the measure seems to be working -- there have been no successful attacks in nearly a year -- the restrictions on the movement of Seychellois fishermen has created another problem .

`` There 's no fish , '' explains local fisherman Patrick Pierre . `` Every boat is fishing in the same place , '' he adds .

Pierre , who 's been casting his nets for 12 years now , says his job was hardest during the worst period of the piracy -- in 2007 and 2008 . Since then , the Seychelles has been at the forefront of the global fight against piracy but the new rules mean fewer fish and less money .

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Joram Madnack is the general manager of the French-owned Indian Ocean Tuna , one of the world 's largest tuna canneries and the biggest employer in the Seychelles . He says fish intake has fallen nearly 25 % in the last five years .

`` The impact has been on the price , which for some places has gone up by 70 % -80 % compared to 2007 prices , '' explains Madnack .

According to a recent report by the World Bank , piracy costs the global economy an estimated $ 18 billion a year . The increased costs come as shippers are forced to change trading routes , sending fuel bills soaring , as well as pay higher insurance premiums and security bills for guards on board .

But the threat of Somali piracy is also damaging the economies of neighboring countries , particularly in the key sectors of tourism and fishing . Since 2006 , the year the World Bank report takes as the starting point of piracy , exports of fish products from piracy-hit countries have declined by 23.8 % . In Seychelles , the impact has been even greater , with exports collapsing by nearly 30 % .

`` We now fish where we are allowed to fish , '' says Peter Sinon , the country 's minister of natural resources and industry . `` It has made the industry more costly in terms of going out there -LSB- and -RSB- be secure to bring in what usually was our daily supply of protein , '' he adds .

Watch video : protecting `` blue gold '' from pirates

And although many of the pirates have now gone , the fishermen say their industry still has n't recovered .

For people like Pierre , the fight against piracy and the introduction of fishing zones has proven to be a double-edged sword .

The protection is still necessary , he says , acknowledging that today he is safer . Yet , he and other local fishermen miss the freedom to sail about and return with a big catch .

`` Five years ago , there was a lot of fish , '' says Pierre . `` We could go anywhere we wanted without the fear of piracy and everything . ''

Teo Kermeliotis contributed to this report .

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Seychelles ' fishermen have been targets of Somali pirates

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Piracy forced authorities to introduce zones that restrict fishermen 's movements

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Attacks have decreased , but restrictions hurt fishing industry